"Gamma-glutamyltranspeptidase (GGT) is a heterodimic enzyme that is generated from the precursor protein through posttranslational processing and catalyzes the hydrolysis of gamma-glutamyl bonds in gamma-glutamyl compounds such as glutathione and/or the transfer of the gamma-glutamyl group to other amino acids and peptides." (16618936)

Detected in fetal and adult kidney and liver, adult pancreas, stomach, intestine, placenta and lung. Isoform 3 is lung-specific. There are several other tissue-specific forms that arise from alternative promoter usage but that produce the same protein [P19440 ];